Exercise ball



FIG. 1 is a perspective view of an exercise ball.

FIG. 2 is a front view of the exercise ball of FIG. 1 .

FIG. 3 is a right side view of the exercise ball of FIG. 1 .

FIG. 4 is a left side view of the exercise ball of FIG. 1 .

FIG. 5 is a back view of the exercise ball of FIG. 1 .

FIG. 6 is a bottom view of the exercise ball of FIG. 1 ; and,

FIG. 7 is a top view of the exercise ball of FIG. 1 .

The broken lines in the drawings illustrate portions of the exercise ball that form no part of the claimed design. The contour lines form no part of the claimed design. 

CLAIM The ornamental design for an exercise ball, as shown and described. 